Pub Date : 2024-11-12Epub Date: 2024-11-03DOI: 10.1021/acs.est.4c07907
Naomi J Farren, Samuel Wilson, Yoann Bernard, Marvin D Shaw, Kaylin Lee, Mallery Crowe, David C Carslaw
We develop a new technique called plume regression where fast response instruments located at the roadside are used to measure exhaust plumes of passing vehicles. The approach is used to generate highly disaggregated vehicle emissions information by vehicle type, which compares well with traditional vehicle emission remote sensing. Additionally, the technique provides valuable new information on ambient concentration source apportionment by vehicle type. The technique is flexible enough to consider a wide range of air pollutants and be deployed at roadside ambient monitoring locations. The new approach is used to quantify emissions and concentration source apportionment for ammonia (NH3) and nitrogen oxides (NOx). We find that emissions of NH3 are generally very well controlled from diesel vehicles including those with selective catalytic reduction systems that use NH3 to reduce emissions of NOx. By contrast, gasoline passenger cars are shown to be the dominant contributor to NH3 emissions, which increase with vehicle mileage. Average fuel-specific NH3 emission factors for gasoline vehicles range from 0.3 to 1.2 g kg-1, while diesel vehicle emission factors remain below 0.06 g kg-1, with the exception of Euro VI buses with the latest regulatory provisions (0.5 g kg-1).
{"title":"An Ambient Measurement Technique for Vehicle Emission Quantification and Concentration Source Apportionment.","authors":"Naomi J Farren, Samuel Wilson, Yoann Bernard, Marvin D Shaw, Kaylin Lee, Mallery Crowe, David C Carslaw","doi":"10.1021/acs.est.4c07907","DOIUrl":"10.1021/acs.est.4c07907","url":null,"abstract":"<p><p>We develop a new technique called <i>plume regression</i> where fast response instruments located at the roadside are used to measure exhaust plumes of passing vehicles. The approach is used to generate highly disaggregated vehicle emissions information by vehicle type, which compares well with traditional vehicle emission remote sensing. Additionally, the technique provides valuable new information on ambient concentration source apportionment by vehicle type. The technique is flexible enough to consider a wide range of air pollutants and be deployed at roadside ambient monitoring locations. The new approach is used to quantify emissions and concentration source apportionment for ammonia (NH<sub>3</sub>) and nitrogen oxides (NO<sub><i>x</i></sub>). We find that emissions of NH<sub>3</sub> are generally very well controlled from diesel vehicles including those with selective catalytic reduction systems that use NH<sub>3</sub> to reduce emissions of NO<sub><i>x</i></sub>. By contrast, gasoline passenger cars are shown to be the dominant contributor to NH<sub>3</sub> emissions, which increase with vehicle mileage. Average fuel-specific NH<sub>3</sub> emission factors for gasoline vehicles range from 0.3 to 1.2 g kg<sup>-1</sup>, while diesel vehicle emission factors remain below 0.06 g kg<sup>-1</sup>, with the exception of Euro VI buses with the latest regulatory provisions (0.5 g kg<sup>-1</sup>).</p>","PeriodicalId":36,"journal":{"name":"环境科学与技术","volume":null,"pages":null},"PeriodicalIF":10.8,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142566665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-12Epub Date: 2024-10-01DOI: 10.1021/acs.est.4c04929
Mingna Zheng, Yanwei Li, Qingzhu Zhang, Wenxing Wang
Commercial herbicides, particularly sulfonylureas, are used worldwide and pose a significant challenge to environmental sustainability. The efficient degradation of sulfonylurea herbicides is critical. SulE, an esterase isolated from the bacterial strain Hansschlegelia zhihuaiae S113, shows degradation activity toward sulfonylurea herbicides. However, the detailed catalytic mechanism remains vague to a large extent. Herein, we decipher the SulEP44R-catalyzed degradation mechanism of sulfonylurea herbicides using hybrid quantum mechanics and molecular mechanics approaches. Our results show that the degradation of sulfonylureas catalyzed by SulEP44R involves four concerted elementary steps. The rate-determining step has an energy barrier range of 19.7-21.4 kcal·mol-1, consistent with the experimentally determined range of 16.0-18.0 kcal·mol-1. Distortion/interaction analysis demonstrates that active-site amino acids play a vital role in the enzymatic catalytic efficacy. The unique architecture of SulEP44R's active site can serve as an excellent template for designing artificial catalysts. Key structural and charge parameters affecting catalytic activity were systematically screened and identified. Based on the elucidated degradation mechanism, several new herbicides with both high herbicidal activity and biodegradability were developed with the aid of a high-throughput strategy. Our findings may advance the application of sulfonylurea herbicides within the framework of environmental sustainability.
{"title":"Enzymatic Degradation toward Herbicides: The Case of the Sulfonylureas.","authors":"Mingna Zheng, Yanwei Li, Qingzhu Zhang, Wenxing Wang","doi":"10.1021/acs.est.4c04929","DOIUrl":"10.1021/acs.est.4c04929","url":null,"abstract":"<p><p>Commercial herbicides, particularly sulfonylureas, are used worldwide and pose a significant challenge to environmental sustainability. The efficient degradation of sulfonylurea herbicides is critical. SulE, an esterase isolated from the bacterial strain <i>Hansschlegelia zhihuaiae</i> S113, shows degradation activity toward sulfonylurea herbicides. However, the detailed catalytic mechanism remains vague to a large extent. Herein, we decipher the SulE<sup>P44R</sup>-catalyzed degradation mechanism of sulfonylurea herbicides using hybrid quantum mechanics and molecular mechanics approaches. Our results show that the degradation of sulfonylureas catalyzed by SulE<sup>P44R</sup> involves four concerted elementary steps. The rate-determining step has an energy barrier range of 19.7-21.4 kcal·mol<sup>-1</sup>, consistent with the experimentally determined range of 16.0-18.0 kcal·mol<sup>-1</sup>. Distortion/interaction analysis demonstrates that active-site amino acids play a vital role in the enzymatic catalytic efficacy. The unique architecture of SulE<sup>P44R</sup>'s active site can serve as an excellent template for designing artificial catalysts. Key structural and charge parameters affecting catalytic activity were systematically screened and identified. Based on the elucidated degradation mechanism, several new herbicides with both high herbicidal activity and biodegradability were developed with the aid of a high-throughput strategy. Our findings may advance the application of sulfonylurea herbicides within the framework of environmental sustainability.</p>","PeriodicalId":36,"journal":{"name":"环境科学与技术","volume":null,"pages":null},"PeriodicalIF":10.8,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142337335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-12Epub Date: 2024-10-03DOI: 10.1021/acs.est.4c02464
Jiannan Cai, Mei-Po Kwan
The neighborhood effect averaging problem (NEAP) is a fundamental statistical phenomenon in mobility-dependent environmental exposures. It suggests that individual environmental exposures tend toward the average exposure in the study area when considering human mobility. However, the universality of the NEAP across various environmental exposures and the mechanisms underlying its occurrence remain unclear. Here, using a large human mobility data set of more than 27 000 individuals in the Chicago Metropolitan Area, we provide robust evidence of the existence of the NEAP in a range of individual environmental exposures, including green spaces, air pollution, healthy food environments, transit accessibility, and crime rates. We also unveil the social and spatial disparities in the NEAP's influence on individual environmental exposure estimates. To further reveal the mechanisms behind the NEAP, we perform multiscenario analyses based on environmental variation and human mobility simulations. The results reveal that the NEAP is a statistical phenomenon of regression to the mean (RTM) under the constraints of spatial autocorrelation in environmental data. Increasing travel distances and out-of-home durations can intensify and promote the NEAP's impact, particularly for highly dynamic environmental factors like air pollution. These findings illuminate the complex interplay between human mobility and environmental factors, guiding more effective public health interventions.
{"title":"The Universal Neighborhood Effect Averaging in Mobility-Dependent Environmental Exposures.","authors":"Jiannan Cai, Mei-Po Kwan","doi":"10.1021/acs.est.4c02464","DOIUrl":"10.1021/acs.est.4c02464","url":null,"abstract":"<p><p>The neighborhood effect averaging problem (NEAP) is a fundamental statistical phenomenon in mobility-dependent environmental exposures. It suggests that individual environmental exposures tend toward the average exposure in the study area when considering human mobility. However, the universality of the NEAP across various environmental exposures and the mechanisms underlying its occurrence remain unclear. Here, using a large human mobility data set of more than 27 000 individuals in the Chicago Metropolitan Area, we provide robust evidence of the existence of the NEAP in a range of individual environmental exposures, including green spaces, air pollution, healthy food environments, transit accessibility, and crime rates. We also unveil the social and spatial disparities in the NEAP's influence on individual environmental exposure estimates. To further reveal the mechanisms behind the NEAP, we perform multiscenario analyses based on environmental variation and human mobility simulations. The results reveal that the NEAP is a statistical phenomenon of regression to the mean (RTM) under the constraints of spatial autocorrelation in environmental data. Increasing travel distances and out-of-home durations can intensify and promote the NEAP's impact, particularly for highly dynamic environmental factors like air pollution. These findings illuminate the complex interplay between human mobility and environmental factors, guiding more effective public health interventions.</p>","PeriodicalId":36,"journal":{"name":"环境科学与技术","volume":null,"pages":null},"PeriodicalIF":10.8,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142363374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-12Epub Date: 2024-10-03DOI: 10.1021/acs.est.4c04512
Kailun Sun, Cornelis A M van Gestel, Hao Qiu
Molybdenum-based nanosheets (NSMoS2) are increasingly applied in various fields and undergoing relevant risk evaluations on subjectively hypothesized toxicity pathways. However, risk assessment should be unbiased and focus on appropriate end points to avoid biased prescreening. Here, we developed an adverse biological outcome screening strategy based on nontargeted functional protein profiles in earthworm (Eisenia fetida) immune cells exposed to NSMoS2 and their ionic counterpart (Na2MoO4). Through this framework, the apoptosis-related processes with distinct mechanisms were rapidly identified and thoroughly validated phenotypically. Specifically, upon exposure to 50 μg Mo/mL Na2MoO4, cellular signaling and energy homeostasis were disrupted within the transcription-translation biological chain. The autophagic pathway was activated, which, together with energy deprivation, phenotypically induced significant autophagy that ultimately led to apoptosis. In contrast, NSMoS2, tested at the same concentration, caused a reprogramming of apoptotic gene and protein expressions. Transcriptome plasticity facilitated the endocytic-adaptive transcriptional profile characterized by cytoskeleton remodeling and lysosome organization/movement under NSMoS2 exposure. Subcellular dynamics further revealed NSMoS2-induced lysosomal damage with a time-sensitive physiological window, ultimately mediating apoptosis. These findings provide a mechanistic and visual understanding of the distinct risk profile of NSMoS2 compared to molybdate, highlighting the importance of integrating nontargeted screening and phenotypic validation in early risk warning.
{"title":"Two-Dimensional Layered Nano-MoS<sub>2</sub> Induces Earthworm Immune Cell Apoptosis by Regulating Lysosomal Maintenance and Function: Toward Unbiased Screening and Validation of Suspicious Pathways.","authors":"Kailun Sun, Cornelis A M van Gestel, Hao Qiu","doi":"10.1021/acs.est.4c04512","DOIUrl":"10.1021/acs.est.4c04512","url":null,"abstract":"<p><p>Molybdenum-based nanosheets (NSMoS<sub>2</sub>) are increasingly applied in various fields and undergoing relevant risk evaluations on subjectively hypothesized toxicity pathways. However, risk assessment should be unbiased and focus on appropriate end points to avoid biased prescreening. Here, we developed an adverse biological outcome screening strategy based on nontargeted functional protein profiles in earthworm (<i>Eisenia fetida</i>) immune cells exposed to NSMoS<sub>2</sub> and their ionic counterpart (Na<sub>2</sub>MoO<sub>4</sub>). Through this framework, the apoptosis-related processes with distinct mechanisms were rapidly identified and thoroughly validated phenotypically. Specifically, upon exposure to 50 μg Mo/mL Na<sub>2</sub>MoO<sub>4</sub>, cellular signaling and energy homeostasis were disrupted within the transcription-translation biological chain. The autophagic pathway was activated, which, together with energy deprivation, phenotypically induced significant autophagy that ultimately led to apoptosis. In contrast, NSMoS<sub>2</sub>, tested at the same concentration, caused a reprogramming of apoptotic gene and protein expressions. Transcriptome plasticity facilitated the endocytic-adaptive transcriptional profile characterized by cytoskeleton remodeling and lysosome organization/movement under NSMoS<sub>2</sub> exposure. Subcellular dynamics further revealed NSMoS<sub>2</sub>-induced lysosomal damage with a time-sensitive physiological window, ultimately mediating apoptosis. These findings provide a mechanistic and visual understanding of the distinct risk profile of NSMoS<sub>2</sub> compared to molybdate, highlighting the importance of integrating nontargeted screening and phenotypic validation in early risk warning.</p>","PeriodicalId":36,"journal":{"name":"环境科学与技术","volume":null,"pages":null},"PeriodicalIF":10.8,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142363376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-12Epub Date: 2024-10-29DOI: 10.1021/acs.est.4c09611
Jun-Jie Zhu, Alexandria B Boehm, Zhiyong Jason Ren
{"title":"Environmental Machine Learning, Baseline Reporting, and Comprehensive Evaluation: The EMBRACE Checklist.","authors":"Jun-Jie Zhu, Alexandria B Boehm, Zhiyong Jason Ren","doi":"10.1021/acs.est.4c09611","DOIUrl":"10.1021/acs.est.4c09611","url":null,"abstract":"","PeriodicalId":36,"journal":{"name":"环境科学与技术","volume":null,"pages":null},"PeriodicalIF":10.8,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142520329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-12Epub Date: 2024-10-31DOI: 10.1021/acs.est.4c10068
Aaifa Chaudhary, Muhammad Usman, Wei Cheng, Stefan Haderlein, Jean-François Boily, Khalil Hanna
Per- and polyfluoroalkyl substances (PFAS) are ubiquitous environmental contaminants that often co-occur with heavy metals. Despite their prevalence, the mobility of PFAS in complex, multicomponent systems, particularly at the molecular scale, remains poorly understood. The vast diversity of PFAS and their low concentrations alongside anthropogenic and natural substances underscore the need for integrating mechanistic insights into the sorption models. This study explores the influence of metal cations (Cu(II), Cd(II), and Fe(II)) on the adsorption of four common PFAS (PFOA, PFOS, PFDA, and GenX) onto goethite (α-FeOOH), a common iron (oxyhydr)oxide in both aquatic and terrestrial environments. PFAS adsorption was highly dependent on the PFAS type, pH, and metal ion concentration, with a surface complexation model effectively predicting these interactions. Cu(II) and Cd(II) enhanced PFOS and PFDA adsorption via ternary complexation while slightly reducing PFOA and GenX adsorption. Under anoxic conditions, Fe(II) significantly increased the adsorption of all PFAS, showing reactivity greater than those of Cu(II) and Cd(II). Additionally, natural organic matter increased PFAS mobility, although metal cations in groundwater may counteract this by enhancing PFAS retention. These findings highlight the key role of metal cations in PFAS transport and offer critical insights for predicting PFAS behavior at oxic-anoxic environmental interfaces.
{"title":"Heavy-Metal Ions Control on PFAS Adsorption on Goethite in Aquatic Systems.","authors":"Aaifa Chaudhary, Muhammad Usman, Wei Cheng, Stefan Haderlein, Jean-François Boily, Khalil Hanna","doi":"10.1021/acs.est.4c10068","DOIUrl":"10.1021/acs.est.4c10068","url":null,"abstract":"<p><p>Per- and polyfluoroalkyl substances (PFAS) are ubiquitous environmental contaminants that often co-occur with heavy metals. Despite their prevalence, the mobility of PFAS in complex, multicomponent systems, particularly at the molecular scale, remains poorly understood. The vast diversity of PFAS and their low concentrations alongside anthropogenic and natural substances underscore the need for integrating mechanistic insights into the sorption models. This study explores the influence of metal cations (Cu(II), Cd(II), and Fe(II)) on the adsorption of four common PFAS (PFOA, PFOS, PFDA, and GenX) onto goethite (α-FeOOH), a common iron (oxyhydr)oxide in both aquatic and terrestrial environments. PFAS adsorption was highly dependent on the PFAS type, pH, and metal ion concentration, with a surface complexation model effectively predicting these interactions. Cu(II) and Cd(II) enhanced PFOS and PFDA adsorption via ternary complexation while slightly reducing PFOA and GenX adsorption. Under anoxic conditions, Fe(II) significantly increased the adsorption of all PFAS, showing reactivity greater than those of Cu(II) and Cd(II). Additionally, natural organic matter increased PFAS mobility, although metal cations in groundwater may counteract this by enhancing PFAS retention. These findings highlight the key role of metal cations in PFAS transport and offer critical insights for predicting PFAS behavior at oxic-anoxic environmental interfaces.</p>","PeriodicalId":36,"journal":{"name":"环境科学与技术","volume":null,"pages":null},"PeriodicalIF":10.8,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142542860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-12Epub Date: 2024-10-28DOI: 10.1021/acs.est.4c07410
Run Tian, Malte Posselt, Kathrin Fenner, Michael S McLachlan
Biodegradation is one of the most important processes influencing the fate of organic contaminants in the environment. Quantitative understanding of the spatial variability in environmental biodegradation is still largely uncharted territory. Here, we conducted modified OECD 309 tests to determine first-order biodegradation rate constants for 97 compounds in 18 freshwater river segments in five European countries: Sweden, Germany, Switzerland, Spain, and Greece. All but two of the compounds showed significant spatial variability in rate constants across European rivers (ANOVA, P < 0.05). The median standard deviation of the biodegradation rate constant between rivers was a factor of 3. The spatial variability was similar between pristine and contaminated river segments. The longitude, total organic carbon, and clay content of sediment were the three most significant explanatory variables for the spatial variability (redundancy analysis, P < 0.05). Similarities in the spatial pattern of biodegradation rates were observed for some groups of compounds sharing a given functional group. The pronounced spatial variability presents challenges for the use of biodegradation simulation tests to assess chemical persistence. To reflect the variability in the biodegradation rate, the modified OECD 309 test would have to be repeated with water and sediment from multiple sites.
{"title":"Variability of Biodegradation Rates of Commercial Chemicals in Rivers in Different Regions of Europe.","authors":"Run Tian, Malte Posselt, Kathrin Fenner, Michael S McLachlan","doi":"10.1021/acs.est.4c07410","DOIUrl":"10.1021/acs.est.4c07410","url":null,"abstract":"<p><p>Biodegradation is one of the most important processes influencing the fate of organic contaminants in the environment. Quantitative understanding of the spatial variability in environmental biodegradation is still largely uncharted territory. Here, we conducted modified OECD 309 tests to determine first-order biodegradation rate constants for 97 compounds in 18 freshwater river segments in five European countries: Sweden, Germany, Switzerland, Spain, and Greece. All but two of the compounds showed significant spatial variability in rate constants across European rivers (ANOVA, <i>P</i> < 0.05). The median standard deviation of the biodegradation rate constant between rivers was a factor of 3. The spatial variability was similar between pristine and contaminated river segments. The longitude, total organic carbon, and clay content of sediment were the three most significant explanatory variables for the spatial variability (redundancy analysis, <i>P</i> < 0.05). Similarities in the spatial pattern of biodegradation rates were observed for some groups of compounds sharing a given functional group. The pronounced spatial variability presents challenges for the use of biodegradation simulation tests to assess chemical persistence. To reflect the variability in the biodegradation rate, the modified OECD 309 test would have to be repeated with water and sediment from multiple sites.</p>","PeriodicalId":36,"journal":{"name":"环境科学与技术","volume":null,"pages":null},"PeriodicalIF":10.8,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142491107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-12Epub Date: 2024-11-01DOI: 10.1021/acs.est.4c08890
Yanfei Tang, Eakalak Khan, Daniel C W Tsang
This study proposes a novel strategy that utilizes biochar (BC) during anaerobic fermentation (AF) to generate amino acids (AAs) toward nitrogen upcycling. The BC, pyrolyzed at 800 °C (BC800) to enhance graphite structures and electron-accepting sites, effectively addresses issues related to biosynthetic reducing power nicotinamide adenine dinucleotide phosphate insufficiency by altering cellular conditions and alleviates feedback inhibition through the immobilization of end products. This process establishes unique microbial signaling and energy networks, with Escherichia coli becoming dominant in the biofilm. The conversion rate of ammonia-N to AAs-N within the biofilm reached 67.4% in BC800-AF, which was significantly higher compared to the levels in other AF reactors with BC pyrolyzed at 600 and 400 °C (45.9 and 22.5%, respectively), as well as a control AF reactor (<5%). Furthermore, in BC800-AF, the aromatic AAs (Aro-AAs) were as high as 70.8% of the AAs within the biofilm. The activities of key enzymes for Aro-AAs biosynthesis uniquely positively correlated with the electron-accepting capacity on BC800 (R2 ≥ 0.95). These findings hold promise for transforming existing AF reactors into factories that produce BC-based AAs, providing a more sustainable fertilizing agent than chemical fertilizers.
本研究提出了一种新策略,即在厌氧发酵(AF)过程中利用生物炭(BC)生成氨基酸(AAs),实现氮的上循环。生物炭在 800 °C(BC800)高温下热解以增强石墨结构和电子接受位点,通过改变细胞条件有效解决了与生物合成还原力烟酰胺腺嘌呤二核苷酸磷酸酯不足有关的问题,并通过固定最终产物缓解了反馈抑制。这一过程建立了独特的微生物信号和能量网络,大肠杆菌在生物膜中占据主导地位。在 BC800-AF 中,生物膜内氨-N 向 AAs-N 的转化率达到 67.4%,与其他在 600 和 400 °C 下热解 BC 的 AF 反应器(分别为 45.9% 和 22.5%)以及对照 AF 反应器(R2 ≥ 0.95)的水平相比显著提高。这些研究结果有望将现有的 AF 反应器改造成生产基于 BC 的 AA 的工厂,提供比化肥更可持续的肥料。
{"title":"Waste Nitrogen Upcycling to Amino Acids during Anaerobic Fermentation on Biochar: An Active Strategy for Regulating Metabolic Reducing Power.","authors":"Yanfei Tang, Eakalak Khan, Daniel C W Tsang","doi":"10.1021/acs.est.4c08890","DOIUrl":"10.1021/acs.est.4c08890","url":null,"abstract":"<p><p>This study proposes a novel strategy that utilizes biochar (BC) during anaerobic fermentation (AF) to generate amino acids (AAs) toward nitrogen upcycling. The BC, pyrolyzed at 800 °C (BC800) to enhance graphite structures and electron-accepting sites, effectively addresses issues related to biosynthetic reducing power nicotinamide adenine dinucleotide phosphate insufficiency by altering cellular conditions and alleviates feedback inhibition through the immobilization of end products. This process establishes unique microbial signaling and energy networks, with <i>Escherichia coli</i> becoming dominant in the biofilm. The conversion rate of ammonia-N to AAs-N within the biofilm reached 67.4% in BC800-AF, which was significantly higher compared to the levels in other AF reactors with BC pyrolyzed at 600 and 400 °C (45.9 and 22.5%, respectively), as well as a control AF reactor (<5%). Furthermore, in BC800-AF, the aromatic AAs (Aro-AAs) were as high as 70.8% of the AAs within the biofilm. The activities of key enzymes for Aro-AAs biosynthesis uniquely positively correlated with the electron-accepting capacity on BC800 (<i>R</i><sup>2</sup> ≥ 0.95). These findings hold promise for transforming existing AF reactors into factories that produce BC-based AAs, providing a more sustainable fertilizing agent than chemical fertilizers.</p>","PeriodicalId":36,"journal":{"name":"环境科学与技术","volume":null,"pages":null},"PeriodicalIF":10.8,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142556597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-12Epub Date: 2024-10-29DOI: 10.1021/acs.est.4c06566
Yuna Gu, Qiancheng Xia, Bin Liu, Yang Zhao, Liangtao Pu, Jie Ding, Yanbiao Liu, Enze Li, Chad D Vecitis, Guandao Gao
Demulsification technology for separation of oil-water (O/W) emulsions, especially those stabilized by surfactants, is urgently needed yet remains highly challenging due to their inherent stability characteristics. Electrocoalescence has emerged as a promising solution owing to its simplicity, efficacy, and versatility, yet hindered by substantial energy consumption (e.g., >50 kWh/m3) along with undesirable Faradic reactions. Herein, we propose an innovative electric demulsification technology that leverages conductive membrane microchannels to confine oil droplets from the oil-water emulsion for achieving high energy-efficient coalescence of oil droplets. The proposed system reduces the required voltage down to 12 V, 2 orders of magnitude lower than that of conventional electrocoalescence systems, while achieving a similar separation efficacy of 91.4 ± 3.0% at a low energy consumption (3 kWh/m3) and an ultrahigh permeability >3000 L/(m2·h·bar). In situ fluorescence microscopy combined with COMSOL simulations provided insight into the fundamental mechanistic steps of an electric demulsification process confined to membrane microchannels: (1) rapid electric-field redistribution of oil droplet surfactant molecules, (2) enhanced collision probability due to confined oil droplet concentration under dielectrophoretic forces, and (3) increased collision efficacy facilitated by the membrane pore structure. This strategy may revolutionize the next generation of demulsification and oil-water separation innovations.
{"title":"Electric Demulsification Membrane Technology for Confined Separation of Oil-Water Emulsions.","authors":"Yuna Gu, Qiancheng Xia, Bin Liu, Yang Zhao, Liangtao Pu, Jie Ding, Yanbiao Liu, Enze Li, Chad D Vecitis, Guandao Gao","doi":"10.1021/acs.est.4c06566","DOIUrl":"10.1021/acs.est.4c06566","url":null,"abstract":"<p><p>Demulsification technology for separation of oil-water (O/W) emulsions, especially those stabilized by surfactants, is urgently needed yet remains highly challenging due to their inherent stability characteristics. Electrocoalescence has emerged as a promising solution owing to its simplicity, efficacy, and versatility, yet hindered by substantial energy consumption (e.g., >50 kWh/m<sup>3</sup>) along with undesirable Faradic reactions. Herein, we propose an innovative electric demulsification technology that leverages conductive membrane microchannels to confine oil droplets from the oil-water emulsion for achieving high energy-efficient coalescence of oil droplets. The proposed system reduces the required voltage down to 12 V, 2 orders of magnitude lower than that of conventional electrocoalescence systems, while achieving a similar separation efficacy of 91.4 ± 3.0% at a low energy consumption (3 kWh/m<sup>3</sup>) and an ultrahigh permeability >3000 L/(m<sup>2</sup>·h·bar). <i>In situ</i> fluorescence microscopy combined with COMSOL simulations provided insight into the fundamental mechanistic steps of an electric demulsification process confined to membrane microchannels: (1) rapid electric-field redistribution of oil droplet surfactant molecules, (2) enhanced collision probability due to confined oil droplet concentration under dielectrophoretic forces, and (3) increased collision efficacy facilitated by the membrane pore structure. This strategy may revolutionize the next generation of demulsification and oil-water separation innovations.</p>","PeriodicalId":36,"journal":{"name":"环境科学与技术","volume":null,"pages":null},"PeriodicalIF":10.8,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142520328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The simultaneous sorption of cations and anions at the mineral-water interface can substantially alter their individual sorption characteristics; however, this phenomenon lacks a mechanistic understanding. Our study provides direct spectroscopic and modeling evidence of the molecular cosorption mechanisms of the cadmium ion (Cd2+) and phosphate (P) on goethite and layered manganese (Mn) oxide of birnessite, through in situ attenuated total reflection Fourier-transform infrared (ATR-FTIR), P K-edge X-ray absorption near-edge structure (XANES) spectroscopy, and surface complexation modeling. Phosphate synergistically cosorbed with Cd on goethite predominantly through P-bridged ternary complexes (≡Fe-P-Cd) and electrostatic interactions at wide pH conditions. Likewise, P and Cd exhibited synergistic cosorption on birnessite by forming P-bridged ternary complexes (≡Mn-P-Cd) and weak competitive sorption at the layer edge sites. As pH and Cd loading increased, the surface P species transitioned from a binary complex to a ternary complex and/or Cd3(PO4)2 precipitate for both goethite and birnessite. Compared to that in solution at pH 8, the formation of Cd3(PO4)2 was inhibited by the presence of goethite and birnessite, ascribed to the specific adsorption of P and Cd, more pronounced in birnessite due to the stronger sorption of Cd at its vacant sites. The discovered cosorption mechanisms of P and Cd have important implications for understanding and predicting their mobility and availability in Cd-contaminated settings.
阳离子和阴离子在矿物-水界面上的同时吸附会大大改变它们各自的吸附特性;然而,人们对这一现象缺乏机理上的认识。我们的研究通过原位衰减全反射傅立叶变换红外光谱(ATR-FTIR)、磷矿石 K 边 X 射线吸收近边结构(XANES)光谱和表面络合模型,提供了镉离子(Cd2+)和磷矿石(P)在鹅绿泥石和层状氧化锰(Mn)的分子协同吸附机制的直接光谱和模型证据。在较宽的 pH 值条件下,磷酸盐主要通过 P 桥接三元络合物(≡Fe-P-Cd)和静电作用与镉协同吸附在鹅卵石上。同样,钯和镉通过形成钯桥接三元络合物(≡锰-钯-镉)以及在层边缘位点的弱竞争吸附作用,在桦锰矿上表现出协同共吸附作用。随着 pH 值和镉负载量的增加,鹅绿泥石和桦褐铁矿的表面 P 物种都从二元络合物转变为三元络合物和/或 Cd3(PO4)2 沉淀。与 pH 值为 8 的溶液相比,Cd3(PO4)2 的形成受到鹅绿泥石和桦绿泥石的抑制,这归因于 P 和 Cd 的特定吸附作用,在桦绿泥石中更为明显,因为 Cd 在其空位上的吸附作用更强。所发现的钾和镉的共吸附机制对于理解和预测它们在镉污染环境中的流动性和可用性具有重要意义。
{"title":"Elucidating Phosphate and Cadmium Cosorption Mechanisms on Mineral Surfaces with Direct Spectroscopic and Modeling Evidence.","authors":"Wantong Zhao, Yun Xu, Liting Gu, Mengqiang Zhu, Peng Yang, Chunhao Gu, Zhe Liu, Xionghan Feng, Wenfeng Tan, Qiaoyun Huang, Xiaoming Wang","doi":"10.1021/acs.est.4c08847","DOIUrl":"10.1021/acs.est.4c08847","url":null,"abstract":"<p><p>The simultaneous sorption of cations and anions at the mineral-water interface can substantially alter their individual sorption characteristics; however, this phenomenon lacks a mechanistic understanding. Our study provides direct spectroscopic and modeling evidence of the molecular cosorption mechanisms of the cadmium ion (Cd<sup>2+</sup>) and phosphate (P) on goethite and layered manganese (Mn) oxide of birnessite, through in situ attenuated total reflection Fourier-transform infrared (ATR-FTIR), P <i>K</i>-edge X-ray absorption near-edge structure (XANES) spectroscopy, and surface complexation modeling. Phosphate synergistically cosorbed with Cd on goethite predominantly through P-bridged ternary complexes (≡Fe-P-Cd) and electrostatic interactions at wide pH conditions. Likewise, P and Cd exhibited synergistic cosorption on birnessite by forming P-bridged ternary complexes (≡Mn-P-Cd) and weak competitive sorption at the layer edge sites. As pH and Cd loading increased, the surface P species transitioned from a binary complex to a ternary complex and/or Cd<sub>3</sub>(PO<sub>4</sub>)<sub>2</sub> precipitate for both goethite and birnessite. Compared to that in solution at pH 8, the formation of Cd<sub>3</sub>(PO<sub>4</sub>)<sub>2</sub> was inhibited by the presence of goethite and birnessite, ascribed to the specific adsorption of P and Cd, more pronounced in birnessite due to the stronger sorption of Cd at its vacant sites. The discovered cosorption mechanisms of P and Cd have important implications for understanding and predicting their mobility and availability in Cd-contaminated settings.</p>","PeriodicalId":36,"journal":{"name":"环境科学与技术","volume":null,"pages":null},"PeriodicalIF":10.8,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142542859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}